Circuit maker and breaker



H. A. SCHLOSSER July 14, 1942.

CIRCUIT MAKER AND BREAKER Filed March 31, 1941 Patented Juli, 1942UNITED STATES PATENT OFFICE Application March 31, 1941, Serial No.386,162

4 Claims.

This invention relates to circuit makers and breakers, and the presentapplication is a continuation-impart of my prior application, Serial No.259,671, filed March 3, 1939, entitled Automatic direction switch, nowmatured into Patent No. 2,241,164, of May 6, 1941.

In the art of electric signaling there are many circuit systems whichhave associated means for effecting intermittent opening. and closing ofa circuit as a function thereof. The present invention has particularutility in this fleld, but is applicable to any system requiring theintermittent make and break of an electrical circuit.

An object of the invention is to provide a circuit maker and breaker ofthe fluid pressure type, having self-contained means for effectingsustained automatic operation thereof to cause intermittent opening andclosing in rapid succession of an electrical circuit with which it isassociated.

Another object is to provide, in a fluid pressure circuit maker andbreaker, control means biased to" inoperative position and movabletherefrom by manual operation, and actuator mechanism that is set inautomatic operation by switch means to and from the initial position.

Related objects include the provision of a novelquick-acting actuatormeans in operativeassociation with the fluid pressure responsive elementof a fluid pressure circuit maker and breaker, and a novel structuralarrangement of control valve and circuit switch. In the drawing: a

Figure l is a schematic representation of a practical embodiment of theinvention.

Figure 2 is substantially a central vertical sectional view through thecircuit maker and breaker shown in elevation in Figure 1.

V Figure 3 is a section taken on the line 33 of Figure 2.

Figure 4 is a section similar to Figure 2, but showing a difierentposition of certain of the parts, assumed in operation.

In detail, the invention comprises a chamber enclosed by twohalf-sections of casing 5 and 6 having mating edge flanges connecting bysecuring elements 1, with a flexible diaphragm 8 clamped therebetweenand dividing the chamber into two non-communicating portions. One casingsection is provided with a central socket 9 that seats spring means IIwhich bears against the diaphragm under a compression urging it in thedirection of the opposite section.

A draw bar I I is secured at its inner end to. the diaphragm center andextends laterally therefrom on the side opposite that against which thespring bears. The bar projects through the adjacent casing wall, whichis apertured to permit its free movement therethrough, and at its outerend is pivotally connected to an ear stud 12 on a strut l3 that extendstransversely between and connects a pair of parallel throw levers. M.The lower ends of the levers have a knife-edge fulcrum bearing in rigidsupport members I5 carried by and projecting from the adjacent casingsection, and at their upper ends the levers are connected by atransverse top bar i6. Preferably, but not necessarily, the levers l4,strut I3, and top bar iii are of integral construction and occupy acommon plane. The assembly of levers, strut, and top bar constitutes, ineffect, a unitary throw member which is a lever pivoted at its lower endto a fixed part of the casing assembly, and which is capable ofoscillation in a vertical plane under propulsion by the draw bar.

That portion of the I diaphragm chamber through which the draw bar lloperates is at all times open to the atmosphere through the draw baraperture in the casing wall, so that fluid pressure therein is constant.The chamber at the other side of the diaphragm is, however, subjected topressure that is variable in accordance with operating movement of valvemeans under both automatic actuation and remote manual control.

The valve means includes a casting i1 rigidly attached to the casingassembly and extending laterally therefrom centrally of its bottom edgeto provide a tubular valve casing having an axial, cylindrical bore l8entirely there- 'through. At one end the valve casing abuts'the edgeflange of the variable pressure chamber, and at its other end is formedwith an internally threaded socket to receive the threaded nipple I9 ofa pipe coupling 20. The bore 21 of the pipe coupling is reduced relativeto" the valve tion of the apparatus parts the inner end of-the valveplug 2'2 seats firmly against the end of the nipple l8 and closes oflcommunication between v the bores 18 and 2|, while the variable pressurechamber is in open communication with the atmosphere through a conduit25 which estab lishes communication between the chamber in teriorthrough the casing section '6 to the bore ll! of the valve casing and alateral-port 23 leading therefrom to the exterior of the valve casing.

The points at which the conduit 25 and port 26 communicate with the bore18 are spaced apart axially of the bore a distance sufllcient so thatwhen the valve 22 is at its extreme open position, shown in Figure 4,the port 26 will be fully closed and the pipe bore 2| will be inunobstructed communication with the conduit 25 from the variablepressure chamber. when the valve isfully closed, as shown in Figure 3, adiametrically reduced portion stem registers with the conduit 25 andport 26 for communication therebetween. while'the conduit is cut oilfrom any communication with the pipe bore 2|. Preferably, the port 23 iscontrolled by a needle valve 23.

The body of the valve plug 22 is of insulating material except for anannular band 29 of electro-conductive material disposed around itsperiphery intermediate the ends, preferably adjacent the inner end ofthe valve. The band 29 retained in their sockets by the positive upwardpull exerted by a pair of contraction springs 4| connected at theirupper ends to the throw lever top bar 16 and at their lower ends to thelater-' ally projecting ends of a cross bar 42 rigidly secured to thelever 31. At its lower end the actuator lever 31 is bifurcated tostraddle the valve 21 of the valve provides a valve carried means forelectrically 1 bridging a pair of diametrically opposed ball and springcontacts and 3| mounted in the usual manner in bushings of insulatingmaterial disposed through the body of the valve casing. The

- contacts are part of an electrical circuit C, in-

dicated generally as also including translating means L and a currentsource B.

The organization shown in Figure 1 illustrates a practical applicationof the'invention in which B is the battery, of an automobile, L is astop light, and the valve stem 23 has a cable connection 32 with a brakepedal 33; a spring connector. 34 being interposed in the cable.- Thepipe coupling 2ll\connects with a tubing line 35 to a vacuum tank 36 inwhich suction is maintained by operation of the motor, not shown.Figures 1 and 3 show the initial, inoperative position of the parts,with the valve 22 closed and retained against its seat by suction in theline 35 and pipe coupling bore 2|.

When the pedal 33 is. advanced to brake applying position apull isexerted on the cable 32 to shift the valve stem and move the valve 22from its seat to fully open position as shown in Figure 4, uncoveringthe mouth of the conduit 25 and subjecting the variable pressure chamberto suction by reason of vacuum in the tank 36 and line 35. As the valvemoves to open position, the bridging member 29 is brought into registrywith the contacts 30 and 3| to close the circuit C and light the lamp L.

Immediately upon the setting up of a vacuurn behind the diaphragm 8, asudden pull is exerted on the draw bar I I by the correspondingfiexingof the diaphragm into the casing .section 6, and the spring 10 iscompressed. The movement' of the drawbar correspondingly rocks the throwlevers I4 into the position shown in'Figure 4. Movement ofthethrow-lever means brings into play a snap action lever 31 which operatesto return the valve 22 to initial closed position and break the circuit,as will be described. v

The lever 31 constitutes a valve actuator, and comprises a flat barhaving at its upper end a guide finger 38 that plays between the outerends of a pair of parallel supports 39 rigidly secured to the casingsection 5 and'extending laterally therefrom. fur-therprovided with knifeedge shoulders 43 which pivot in fulcrum sockets in the under The upperend of the bar is stem 23 with suflicient clearance to permit free swingof the lever over and along the valve stem andto provide arm portions 43adapted to engage a cross pin abutment 44 carried by the valve stem. Thelever 31 oscillates in a vertical plane; its extent of outward swingbeing limited by a stirrup member 45 attached to the casin assembly, andits inward swing being limited by the throw lever strut l3.

It will be noted that the pivot oi the actuator lever 31 is above thepivot point of the throw lever l4 and laterally offset relative theretooutwardly from the casing; also, that motive power is applied to thelever 31 from the springs 4| at a pointabove the fulcrum of the throwlever. In the rocking of the throw-lever assembly, its top bar I6 passesabove the fulcrum of the actuator lever in the supports 39, so that, asit passes deadcenter, the pull of the springs rocks the actuator lever31 with a quick snap action.

In operation, when the valve 22 moves to open position its stem abutment44 moves correspondingly until it engages the inner face of the lowerend portion of the actuator lever 31 which, being held by the stirrup 45arrests further movement of the valve. Duringopening travel of the valvethe circuit will have been first closed and then opened acrossv thecontacts 30 and 3|. When the valve reaches fully open position toestablish a vacuum behind the diaphragm as explained, the pull of thedraw bar I I rocks the throw lever assembly which, in turn, rocks theactuator lever 31 with a quick snap action that kicks the valve stemabutment 44 inwardly and thus returns the valve to initial closedposition; during which movement the circuit will once again have beenmade and broken. The force exerted by the actuator lever is suflicientto overcome the tension of the spring connector 34 in the brake pedalcable, but when the lever comes to rest the pull of the spring, as itcontracts, pulls the valve back again to open position, which againopens and closes the circuit. It will be understood that I exerted bythe actuator lever 31 in returning the valve to closed position.

As soon as the valve returns to initial closed position, the exhaustedvariable pressure chamber is opened to the atmosphere through theconduit 25 and port 26, so that pressure at both sides of the diaphragmbecomes equal. The equalization of pressure permits expansion of thespring It to push the draw bar outwardly, whereupon the throw leverassembly is rocked to snap the actuator lever 31 back against thestirrup 45 in its initial position, freeing it from the valve stemabutment 44. The valve immediately starts to open, under pull of thespring 34, and in moving to open position it again makes and breaks theof the valve continues rapidly and automatically so long as the brakepedal 33 is held in brake. applying position, and the stop light L isthus caused to flash on and oil by the continuous making and breaking ofthe circuit. This con-,

dition endures until the brake pedal is released,

whereupon the parts reassume their initial positions, with the valv 22closed and the circuit broken. The valve is normally retained in closedposition against its seat by the urge of suction acting in the line 35to bias the valve closed position.

It is to be understood that; within th scope of the invention asclaimed, the structural details and arrangement of parts hereindisclosed may be varied as desired. The illustrated pedal 33' isrepresentative of any means manually operative to accomplish work; thediaphragm is rep-- resentative of any fluid pressure responsive means;the valve 22, chamber assembly. vacuum line and tank may be any meansfor establishing of the pressure responsive means to effect automaticoperation of the valve and switch; and the cable 32 with spring 34 is aremote control connection between the member 33 and the means forestablishing fluid pressure differences.

I claim:

1. Electrical circuit control means comprising a member movable inresponse to difference in a pressure. other than atmospheric whereby toflex said diaphragm, said valve having an operating stem, an actuatorleverfulcrumed on the casing structure to oscillate longitudinally oithe valve stem, an operating member secured to said diaphragm formovement therewith as it.

flexes, quick throw means connecting said operating member and lever foroscillation of the lever on movement of the operating member, andcooperative means on said lever and valve stemengageable to shift thevalve stem in one direction. during oscillation of the lever, said avalve having an electro-conductive portion, and

fluid pressure at opposite sides thereof, means], biased to a normalposition establishing a presj sure balance'at opposite sides of themember and being movable to a limit position establishing a pressuredifference between opposite sides of the member whereby to causemovement of the member, a circuit switch connected with said means toopen and close as said means is moved, a. manual control member movableto work position, an operating connection between said control memberand the pressure establishing means for moving said means to its limitposition on movement of the control member to work po: sition, saidoperating connection including a resilient member, mechanism connectedto and operative by movement of the pressure responsive member to engageand restore said pressure establishing means to its normal positionagainst tension imposed by said resilient member, and means operativeupon balancing of pressure on the pressure responsive member to releasesaid mechanism to permit said resilient member to again move thepressure establishing means to its limit position.

2- A circuit maker and breaker comprising a diaphragm flexible inaccordance with variations in fluid pressure on opposite sides thereof,a

casing enclosing said diaphragm to form nonoommunicating chambers onopposite sides thereof, one chamber being open to the atmosphere, aconduit leading from the other chamber, a valve controlling said conduitand being shiftable to one position opening said conduit to theatmosphere and to another position closing said conduit to theatmosphere and placing said conduit in communication with a source offluid pressure other than atmospheric thereby permitting theestablishment in its chamber of normally separated circuit contactsadapted to be bridged by said conductive portion during movement of thevalve.

3. Electrical circuit control means comprising 'a source of fluidpressure, a fluid pressure operated device, valve means controllingcommunication between said source of fluid pressure and said pressureoperated device, acontrol member manually movable to operative andinoperative positions, a mechanical connection including a spring memberbetween said control member 'and said valve means adapted, upon movementof said control member to operative position to open said valve means toactuate said'pressure operated device, a linkage between said pressureoperated device and said valve means operative, upon actuation of saidpressure operated device, to return said valve to closed positionagainst the opposition of said spring member and to relieve the pressurefrom said pressure operated device whereupon said spring member causesreopening of said valve means and the opening and closing of said valvemeans continues so long as said control member remains in operativeposition, said valve means includin an electrical circuit controloperative to make and break an electrical upon each opening and Iclosing of said valve means.

4. Electrical circuit control means comprising a casing, a flexiblediaphragm dividing the interior thereof into two non-communicatingchambers, a valve casing on the diaphragm casing and having an axialbore in communication with a fluid pressure line, a valve slidable insaid bore to open and close the fluid pressure line, a conduitestablishing communication between a chamber at one side of thediaphragm and the valve casing bore, said valve casing having a portopening from its bore to the atmosphere, said valve when in openposition placing the conduit in communication with the fluid pressureline through the bore and when in closed. position placing the conduitin communication with said port through the bore, a. stern for op--erating said valve and projecting beyond an end of the valve casing, asupport on the diaphragm casing, an actuator lever pivoted at one end onsaid'support, the other end of said lever having a portion looselystraddling the valve stem, an abutment on' the stem engageable by saidlever portion to move the valve and stem with the lever as it moves in,one direction, a draw bar secured to the diaphragm, a snap throw leverpivoted at one end on the casing, said draw bar having pivotalconnection with the snap lever intermediate its ends, and spring meansconnecting the free end portion of the snap' lever with an intermediateportion of the actuator lever, said valve including means for making andbreaking a circuit as the valve is moved.

HENRY A. SCI-ILOSSER.

